1. Field of the Invention
The present invention relates to a fingerprint reading device a method thereof.
2. Related Background Art
Some of the systems for authenticating an individual for the purpose of keeping confidentiality, etc. have hitherto used an ID number, a password and so on, however, it was not perfect to maintain the confidentiality because the ID number and the password might leak out. While on the other hand, a system using a fingerprint reading device is proposed as that capable of keeping the confidentiality at a much higher level.
There were hitherto proposed electrostatic capacity type fingerprint reading devices (Japanese Patent Application Laid-Open No. Hei4-231803, etc.) for detecting a fingerprint pattern by utilizing the fact that electrostatic capacities occurred between a group of electrodes arranged in a two-dimensional array and a finger touching on the electrode group through a dielectric substance layer differ corresponding to a ruggedness of the fingerprint. This type of fingerprint reading devices has been utilized.
Further, for example, there was proposed an optical fingerprint reading device using an image sensor such as CCD.
There was not, however, a well-designed application about what sort of apparatus incorporates such type of fingerprint reading device and how the fingerprint reading device is used, and very few fingerprint reading devices have been utilized. Moreover, in the case of the optical type, there arises a problem in which the costs are comparatively high and the structure is complicated.